Colour: 3D printing’s grey area

French cubism artist and forerunner to the pop art movement, Fernand Léger once said: “Man needs colour to live; it's just as necessary an element as fire and water”. As humans we see and live in colour. Though the way we interpret various shades and tones may differ per each set of eyes, colour plays a pivotal role in our visual experiences.

There are millions of colours on the International Color Consortium (ICC) designed to function seamlessly across all software, yet 3D printing technology varies in the number we have access to. If we see the world in full, vibrant colour, why are we often restricted to a basic palette?

We spoke to the colour 3D printing experts across materials, software and hardware to find out why colour is so important.

Conor MacCormack, Co-founder and CEO of Mcor Technologies told us what makes 3D printing in colour such a hot topic.

“We all see in colour. Designers design in colour and there’s even evidence that we dream in colour,” Conor explained. “If you print out a standard part that’s either in white or any one solid colour and then you add a full bitmap image it just adds so much more detail. I think it’s because we have evolved as humans, we see colour and we see detail. I think colour is becoming more and more important, especially, when you move into the consumer segments.”

Mcor is the only paper based 3D printing company on the market. Invented by engineers with the idea that it might be “cool to make it in colour”, Mcor IRIS colour technology works using paper and ink whereby a detailed bitmap image is printed onto the part creating photorealistic colour with ICC colour mapping.

Conor continued: “We feel that 3D printing in colour has a long way to go to get to the same standard as 2D printed colour but now that the colour is getting really strong. For us its becoming more and more important but you need to be able to tie it in to the international colour standard ands that what we did.”

Competing with 2D

Moving colour technology from the 2D space into 3D is one of the industry’s biggest challenges. As the technology matures, users expect the same colour quality they are used to experiencing with traditional 2D printing. Mike Scrutton, Senior Product Development Manager at design software pioneer Adobe explained how carrying information through the entire process from 3D design down to the finished printed part is key to achieving accurate colour representation.

“One of the interesting lessons we’ve learned in the conventional 2D printing space is the need to have continuity of accurate information all the way through a workflow,” Mike explained. “There are so many parallels there that people are almost saying to us ‘we really want you to bring everything that you did for the 2D industry and help us with some of the problems we’re facing in 3D’.”

×

Full colour is a widely contested definition and current technology that holds the label tends to be received by a mixed reception from the rest of the industry. But full colour is a big ask with engineers effectively competing against ink jet printers in the 2D spectrum. From machines that offer 60 colours to those that provide thousands of digital materials making the same claim, can they both be full colour? From a software point of view, Mike argues it is about having full control over colour and where it belongs on a product.

“We did marbling at school and we tie dyed T-shirts,” Mike added. “The tie dye T-shirts were extremely colourful but we had next to no control as the to design that we were putting onto those t shirts so it was very colourful but we didn’t really have control of where that colour went. When we talk about full colour in 3D printing we’re talking about not just a part that can be something other than a base material like a white or grey or clear but actually something where a designer gets to accurately choose exactly what colour they want and where they want to put it on their 3d model.”

Conor says Mcor has the same expectations: “When we talk about full colour it has to be any colour at any time so at any point in the model from pixel to pixel it needs to be able to change from one colour to any of the millions of colours available and only then can you claim that it’s full colour.”

Colour as a desktop tool

At this year’s International CES we were introduced to Spectrom, a full colour attachment for desktop FFF 3D printers, which can be plugged seamlessly into most open source 3D printers. Teaming with Robo 3D to develop the technology, Spectrom is about using colour as an additional tool for 3D printing and is set to go into beta testing in the next few months.

Spectrom’s Co-founder, Cédric Kovacs-Johnson explained: “What really excites us is colour as a tool and the people that use 3D printers right now for work, prosumers and engineers, they’re starting to migrate to these desktop machines. This is where all the dirty work and prototyping happens. Colour as a tool brings such a new element beyond just the aesthetics. So for example an engineer with a complex assembly of parts can import that and easily have each component be a different colour.”

Spectrom is a dye-based process, which takes place pre-extrusion allowing the user to have complete control over colour application, resulting in a predictable and precise print. The technology is based on three aims:

“First we needed to be able to reproduce nearly any colour in the spectrum,” Cedric revealed. “Second we needed to have the colour fully integrated so we wanted the colour to be as true as filament you might buy from the store. Third, we wanted the colour to transition in and out extremely quickly and precisely so that would give us the control to do multiple colours per layer.”

The idea of bringing full colour to the desktop is an exciting development for the consumer market which so far has felt limited to a basic range of colour options. Launching in 2011 with a background in materials science and product design, Faberdashery is a company that specialises in providing a range of unique coloured, bioplastic filaments to the desktop market.

“Colour range is really important,” explained Dr. Andrew Dent, Technical Director at Faberdashery. “The key thing is that most of our customers aren’t simply using the technology for rapid prototyping. People are really using the technology for true digital manufacturing so the objects and the items they’re producing are the final pieces. What’s unique about what we do is we’re trying to design materials and particularly colours that are going to be useful for specific applications.”

Faberdashery 'Aurora' filament.

Working with an expert colour-matching lab to manufacture bespoke Pantone colours, all colour formulation for Faberdashery’s 40 plus 3D printing filaments is done in-house without off the shelf colorants. Each colour usually represents around six months of development and can sometimes undergo around 10 iterations.

“For us each colour has to have a story,” Andrew added. “Our starting point is perhaps not a specific colour but sometimes it’s the narrative. For instance Aurora, one of our filaments that changes from a pink by daylight to neon blue under ultraviolet light, we were really interested in that storytelling of how things could transform depending on properties of light. There’s a lot of thought that goes into the development of our colours.”

Colour is about identity

Brand identity is something that has been made increasingly important in regards to colour 3D printing. Colour can be a crucial factor to a brand’s character – think distinctive Coca Cola red - and getting that right down the exact colour code or shade is crucial to conveying a brand message.

Mike commented: “Where companies are using 3D printing to prototype models which are going to represent their brand it’s very important to have those brand colours represented on that final model. People have very clear expectations so being able to reproduce colours accurately is very important to those brands.”

Shapeways is a company familiar with the importance of brand identity, striking up key partnerships with the likes of global toy manufacturer Hasbro. As the world’s leading 3D printing marketplace, the expectations from those products are extremely high.

“With colour it’s not just about what you see on the screen it’s that every set of eyes sees colour differently,” Savannah Peterson, Director of Global Community, Shapeways, said. “I think you see that challenge in the world exacerbated when it comes to actually creating your own products.”

Raphael Stargrove, Materials Product Manager, Shapeways, added: “I think with colour a lot of it is around content generation. Content generation comes more traditionally from video games, movies. That isn’t necessarily the easiest way to make colour content. Right now these printers act like desktop printers but as we start looking forward to multi material printers we’re going to need a lot more development in through and through colour, voxel based colour and more intuitive ways of actually defining colour.”

A step in the right direction

On the industrial side, the first company in the UK to introduce multi-material 3D printing to its machine portfolio, service provider IPF has been offering full colour 3D printing to several industries and most famously, to the big screen – 3D printed Starlord mask anyone? Gary Miller, Head of 3D Printing and Rapid Prototyping at IPF explained why developments in colour are the next obvious step for the technology.

“We’re printing with three colours, cyan yellow and magenta,” Gary noted. “You can add white to that but we have to sacrifice one of those colours. What we need and what I’m sure is being worked upon in research and development is the introduction of white and black so we’ve got CYMK, the full colour spectrum. That’s clearly got to be the next stage and once that’s here the demand will be even greater.”

The chief members of the IPF team are Robbie, Fred, Barney, Trevor, Colin, Leo and Carol – IPF’s range of high-performance Stratasys machines including the Objet Eden350V, Objet500 Connex and Connex 3. Printing in multiple materials and colours, Gary says its opened customer’s eyes up to the possibilities of the technology but there is still a long way to go.

“Some people focus too much on perfection but it’s another step in the right direction,” Gary commented. “These technologies are moving very quickly now and what seems like it takes ages to filter through, it’s not. 10 years ago I was printing with one material, now I’ve got over 2000 with colour, flexible, different shore hardness’s in different colours, it’s a lot and that’s only in a decade. It’s really gathering momentum now.”

Advances in software to improve the transition of colour information and perhaps even a new file format are a key focuses across the industry. The demand for new materials to increase the range of colours and developments from manufacturers to provide a better colour gamut are going to be crucial in providing not just more colourful but true, full colour 3D printing.